Ib qhov tseeb algorithm rau kev daws qhov teeb meem hauv chemistry yog ib txoj hauv kev zoo los kho qhov kev xeem zaum kawg hauv qhov kev qhuab qhia nyuaj. Hauv xyoo 2017, kev hloov pauv tseem ceeb tau ua rau cov qauv ntawm qhov kev xeem, cov lus nug nrog ib lo lus teb raug tshem tawm ntawm thawj feem ntawm qhov kev xeem. Cov lus ntawm cov lus nug yog muab nyob rau hauv xws li ib txoj kev uas cov kawm tiav qhia kev paub nyob rau hauv ntau yam, piv txwv li, chemistry, thiab tsis yooj yim muab ib tug "zuam".
Kev Sib Tw Tseem Ceeb
Qhov nyuaj tshaj plaws rau cov neeg kawm tiav yog cov lus nug ntawm kev muab cov qauv ntawm cov organic tebchaw, lawv tsis tuaj yeem sau cov algorithm los daws qhov teeb meem.
Yuav daws qhov teeb meem li cas? Txhawm rau tiv nrog txoj haujlwm tau hais tseg, nws yog ib qho tseem ceeb kom paub cov algorithm rau kev daws teeb meem hauv chemistry.
Qhov teeb meem tib yam yog ib yam rau lwm yam kev qhuab qhia.
Ib ntu ntawm kev ua
Feem ntau yog cov teeb meem ntawm kev txiav txim siab qhov sib xyaw los ntawm cov khoom siv hluav taws xob paub, yog li peb xav kom xav txog cov txheej txheem rau kev daws teeb meem siv piv txwvhom kev tawm dag zog no.
1. Tus nqi ntawm cov molar loj ntawm cov khoom muab yog txiav txim siab siv cov txheeb ze txheeb ze rau qee cov roj (yog tias tam sim no nyob rau hauv cov xwm txheej ntawm txoj haujlwm tau npaj tseg).
2. Peb xam tus nqi ntawm cov khoom tsim nyob rau hauv cov txheej txheem no los ntawm cov molar ntim rau ib tug gaseous compound, los ntawm qhov ceev los yog loj rau kua tshuaj.
3. Peb xam qhov muaj nuj nqis ntawm tag nrho cov atoms nyob rau hauv cov khoom ntawm ib tug muab tshuaj tiv thaiv, thiab kuj xam cov loj ntawm txhua.
4. Peb sau cov txiaj ntsig no, tom qab ntawd sib piv cov nqi tau nrog qhov loj ntawm cov organic compound muab los ntawm qhov xwm txheej.
5. Yog tias thawj qhov loj tshaj qhov tau txais, peb txiav txim siab tias oxygen muaj nyob rau hauv lub molecule.
6. Peb txiav txim siab nws pawg, rho tawm rau qhov no los ntawm qhov muab huab hwm coj ntawm cov organic compound tus lej ntawm tag nrho cov atoms.
6. Nrhiav tus naj npawb ntawm cov pa atoms (hauv moles).
7. Peb txiav txim siab qhov sib piv ntawm qhov ntau ntawm tag nrho cov atoms tam sim no hauv qhov teeb meem. Peb tau txais cov qauv ntawm tus ntsuas.
8. Peb sau nws cov qauv molecular, molar mass.
9. Yog tias nws txawv ntawm tus nqi tau txais hauv thawj kauj ruam, peb nce tus naj npawb ntawm txhua lub atom los ntawm ib tus lej ntawm lub sijhawm.
10. Sau cov mis molecular ntawm cov khoom xav tau.
11. Txhais cov qauv.
12. Peb sau qhov sib npaug ntawm cov txheej txheem qhia siv cov qauv ntawm cov organic tshuaj.
Cov txheej txheem npaj los daws qhov teeb meem yog tsim nyog rau txhua txoj haujlwm ntsig txog kev muab cov mis ntawm cov organic compound. Nws yuav pab cov menyuam kawm ntawv theem siabtxaus tiv nrog kev xeem.
Example 1
Yuav ua li cas daws teeb meem algorithmic zoo li?
Yuav teb lo lus nug no, ntawm no yog cov qauv ua tiav.
Thaum hlawv 17.5 g ntawm qhov sib xyaw, 28 litres ntawm carbon dioxide tau txais, nrog rau 22.5 ml ntawm dej vapor. Qhov vapor ntom ntawm cov tshuaj no sib raug rau 3.125 g / l. Muaj cov ntaub ntawv hais tias cov tshuaj ntsuam xyuas yog tsim thaum lub sij hawm lub cev qhuav dej ntawm tertiary saturated cawv. Raws li cov ntaub ntawv muab:
1) ua qee cov kev suav uas yuav tsum tau nrhiav cov mis molecular ntawm cov organic tshuaj no;
2) sau nws cov qauv molecular;
3) ua kom pom cov qauv ntawm thawj qhov sib xyaw ua ke, tshwj xeeb uas cuam tshuam txog kev sib txuas ntawm atoms hauv cov lus thov molecule.
Task data.
- m (pib khoom)- 17.5g
- V carbon dioxide-28L
- V dej-22.5ml
Formulas for lej suav:
- √=√ mn
- √=m/ρ
Yog koj xav tau, koj tuaj yeem tiv nrog txoj haujlwm no ntau txoj hauv kev.
thawj txoj kev
1. Txiav txim siab tus naj npawb ntawm moles ntawm tag nrho cov khoom ntawm cov tshuaj tiv thaiv siv molar ntim.
nCO2=1.25 mol
2. Peb nthuav tawm cov ntsiab lus ntau ntawm thawj lub ntsiab lus (carbon) hauv cov khoom ntawm cov txheej txheem no.
nC=nCO2=, 25 mol
3. Xam qhov loj ntawm lub caij.
mC=1.25 mol12g/mol=15g.
Txiav txim siab qhov loj ntawm cov dej vapor, paub tias qhov ntom yog 1g / ml.
mH2O is 22.5g
Peb nthuav tawm cov khoom siv tshuaj tiv thaiv (dej vapor).
n dej=1.25 mol
6. Peb suav cov ntsiab lus ntau ntawm cov khoom (hydrogen) hauv cov khoom siv tshuaj tiv thaiv.
nH=2n (dej)=2.5 mol
7. Txiav txim siab qhov loj ntawm lub caij no.
mH=2.5g
8. Cia peb suav cov pawg ntawm cov ntsiab lus los txiav txim qhov muaj (tsis muaj) ntawm oxygen atoms hauv lub molecule.
mC + mH=1 5g + 2.5g=17.5g
Qhov no sib raug rau cov ntaub ntawv ntawm qhov teeb meem, yog li ntawd, tsis muaj oxygen atoms hauv cov khoom organic uas xav tau.
9. Nrhiav qhov ratio.
CH2is the simplest formula.
10. Xam M ntawm cov khoom xav tau siv qhov ceev.
M tshuaj=70 g/mol.
n-5, tshuaj zoo li no: C5H10.
Tus mob hais tias cov tshuaj tau los ntawm lub cev qhuav dej ntawm cawv, yog li ntawd, nws yog alkene.
kev xaiv thib ob
Cia peb xav txog lwm qhov kev daws teeb meem.
1. Paub tias cov khoom no tau los ntawm lub cev qhuav dej ntawm cov cawv, peb xaus lus tias nws yuav yog cov chav kawm ntawm alkenes.
2. Nrhiav tus nqi M ntawm cov khoom xav tau siv qhov ceev.
M in=70 g/mol.
3. M (g / mol) rau ib qho compound yog: 12n + 2n.
4. Peb xam tus nqi ntawm cov pa roj carbon atom hauv ib qho ethylene hydrocarbon molecule.
14 n=70, n=5, yog li cov molecularcov formula ntawm ib yam khoom zoo li: C5H10n.
Cov ntaub ntawv rau qhov teeb meem no hais tias cov khoom yog tau los ntawm lub cev qhuav dej ntawm tertiary cawv, yog li nws yog alkene.
Yuav ua li cas thiaj ua tau ib qho algorithm los daws qhov teeb meem? Cov tub ntxhais kawm yuav tsum paub yuav ua li cas thiaj li tau txais cov neeg sawv cev ntawm cov chav kawm sib txawv ntawm cov organic tebchaw, muaj lawv cov tshuaj tshwj xeeb.
Example 2
Cia sim txheeb xyuas qhov kev daws teeb meem siv lwm tus piv txwv los ntawm USE.
Nrog tag nrho combustion ntawm 22.5 grams alpha-aminocarboxylic acid nyob rau hauv atmospheric oxygen, nws muaj peev xwm mus sau 13.44 litres (N. O.) carbon monoxide (4) thiab 3.36 L (N. O.) ntawm nitrogen. Nrhiav cov mis ntawm cov kua qaub.
Data by condition.
- m(amino acids) -22.5 g;
- √(carbon dioxide ) -13.44 litres;
- √(nitrogen) -3, 36 y.
Formula.
- m=Mn;
- √=√ mn.
Peb siv tus qauv algorithm los daws qhov teeb meem.
Nrhiav tus nqi ntawm cov khoom sib cuam tshuam.
(nitrogen)=0.15 mol.Sau qhov sib npaug tshuaj (peb siv cov qauv dav dav). Tsis tas li ntawd, raws li cov tshuaj tiv thaiv, paub txog cov tshuaj, peb suav cov moles ntawm aminocarboxylic acid:
x - 0.3 mol.
Xaiv cov molar pawg ntawm cov aminocarboxylic acid.
M(pib tshuaj )=m/n=22.5 g / 0.3 mol=75 g / mol.
Xaiv cov molar loj ntawm tus thawjaminocarboxylic acid siv cov txheeb ze atomic masses.
M(amino acids )=(R+74) g/mol.
lej txiav txim siab cov hydrocarbon radical.
R + 74=75, R=75 - 74=1.
Los ntawm kev xaiv, peb txheeb xyuas qhov sib txawv ntawm cov hydrocarbon radical, sau cov qauv ntawm qhov xav tau aminocarboxylic acid, tsim cov lus teb.
Yog li ntawd, qhov no tsuas muaj hydrogen atom xwb, yog li peb muaj cov mis CH2NH2COOH (glycine).
Answer: CH2NH2COOH.
Alternative solution
Qhov thib ob algorithm rau kev daws qhov teeb meem yog raws li hauv qab no.
Peb suav cov lus qhia ntau ntawm cov khoom siv tshuaj tiv thaiv, siv tus nqi ntawm cov molar ntim.
(carbon dioxide )=0.6 mol.Peb sau cov txheej txheem tshuaj, ua tub rog nrog cov qauv dav dav ntawm chav kawm ntawm cov khoom sib txuas. Peb xam los ntawm qhov sib npaug ntawm tus lej ntawm cov moles ntawm cov aminocarboxylic acid:
x=0.62 / hauv=1.2 /in mol
Tom ntej, peb suav cov molar loj ntawm aminocarboxylic acid:
M=75 in g/mol.
Siv cov txheeb ze atomic masses ntawm cov ntsiab lus, peb pom cov molar loj ntawm cov aminocarboxylic acid:
M(amino acids )=(R + 74) g/mol.
Sib npaug cov molar pawg, tom qab ntawd daws qhov sib npaug, txiav txim siab tus nqi ntawm cov radical:
R + 74=75v, R=75v - 74=1 (take v=1).
Los ntawm kev xaiv nws los txog rau qhov xaus tias tsis muaj hydrocarbon radical, yog li qhov xav tau amino acid yog glycine.
Yog li ntawd, R=H, peb tau txais cov qauv CH2NH2COOH(glycine).
Answer: CH2NH2COOH.
Kev daws teeb meem zoo li no los ntawm txoj kev ntawm algorithm tsuas yog ua tau yog tias tus menyuam kawm ntawv muaj kev txawj lej txaus txaus.
Programming
Cov algorithms zoo li cas ntawm no? Piv txwv ntawm kev daws teeb meem hauv kev qhia xov xwm thiab khoos phis tawj thev naus laus zis yuav tsum tau ua raws li qhov tseeb ntawm kev ua.
Thaum qhov kev txiav txim raug ua txhaum, ntau yam kev ua yuam kev tshwm sim uas tsis tso cai rau lub algorithm ua haujlwm tag nrho. Tsim ib qho kev pab cuam uas siv cov phiaj xwm taw qhia muaj ob kauj ruam:
- tsim GUI hauv qhov pom kev;
- code development.
Txoj hauv kev no ua kom yooj yim rau cov algorithm rau kev daws teeb meem kev ua haujlwm.
Manually nws yuav luag tsis yooj yim sua kom tswj cov txheej txheem siv sijhawm.
Zoo kawg
Tus qauv algorithm rau kev daws teeb meem kev tsim khoom tau nthuav tawm hauv qab no.
Qhov no yog qhov tseeb thiab nkag siab ua ntu zus. Thaum tsim nws, nws yuav tsum muaj cov ntaub ntawv thawj zaug ntawm txoj haujlwm, thawj lub xeev ntawm cov khoom piav qhia.
Yuav kom qhia txog cov theem ntawm kev daws teeb meem ntawm algorithms, nws yog ib qho tseem ceeb rau kev txiav txim siab lub hom phiaj ntawm kev ua haujlwm, txhawm rau hais txog cov txheej txheem ntawm cov lus txib uas yuav ua tiav los ntawm tus thawj coj.
Tus tsim algorithm yuav tsumua ib qho khoom tshwj xeeb:
- discreteness (pab ua cov kauj ruam);
- uniqueness (txhua qhov kev txiav txim muaj ib qho kev daws teeb meem);
- kev xav;
- kev ua tau zoo.
Ntau lub algorithms loj heev, uas yog, lawv tuaj yeem siv los daws ntau yam haujlwm zoo sib xws.
Ib hom lus programming yog cov txheej txheem tshwj xeeb rau kev sau cov ntaub ntawv thiab cov qauv algorithmic. Tam sim no, nws yog siv nyob rau hauv tag nrho cov scientific teb. Nws qhov tseem ceeb yog ceev. Yog hais tias lub algorithm qeeb, tsis tau lees tias muaj kev xav thiab cov lus teb ceev, nws raug xa rov qab rau kev kho dua.
Lub sijhawm ua tiav ntawm qee qhov haujlwm tau txiav txim siab tsis yog los ntawm qhov loj ntawm cov ntaub ntawv nkag, tab sis kuj los ntawm lwm yam. Piv txwv li, lub algorithm rau sorting ib tug tseem ceeb ntawm cov integers yog yooj yim dua thiab sai dua, muab hais tias ib tug ua ntej sorting tau ua tiav.
